package chapter3.eg2;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;

public class EchoServer {

  public void bind(int port) throws InterruptedException {
    EventLoopGroup bossGroup = new NioEventLoopGroup();
    EventLoopGroup workerGroup = new NioEventLoopGroup();
    try {
      ServerBootstrap bootstrap = new ServerBootstrap();
      bootstrap.group(bossGroup, workerGroup)
          .channel(NioServerSocketChannel.class)
          .option(ChannelOption.SO_BACKLOG, 1024)
          .handler(new LoggingHandler(LogLevel.INFO))
          .childHandler(new ChannelInitializer<SocketChannel>() {
            @Override
            protected void initChannel(SocketChannel ch) throws Exception {
              String delimiter = "_$";
              ch.pipeline().addLast(new DelimiterBasedFrameDecoder(1024,
                  Unpooled.wrappedBuffer(delimiter.getBytes())));
              ch.pipeline().addLast(new StringDecoder());
              ch.pipeline().addLast(new DelimiterBasedFrameEncoder(delimiter));
              ch.pipeline().addLast(new EchoServerHandler());
            }
          });

      ChannelFuture future = bootstrap.bind(port).sync();
      future.channel().closeFuture().sync();
    } finally {
      bossGroup.shutdownGracefully();
      workerGroup.shutdownGracefully();
    }
  }

  public static void main(String[] args) throws InterruptedException {
    new EchoServer().bind(8080);
  }
}
